FIELD OF THE INVENTION
[0001] The present invention relates to absorbent articles which include one or more components
that have been treated with a hydrophobic surface coating intended to render such
components impermeable to liquids having relatively low surface tensions.
BACKGROUND OF THE INVENTION
[0002] The main purpose of consumer utilization of disposable absorbent articles such as
diaper, training pants, sanitary napkins, pantiliners, and adult incontinence articles
is to absorb and contain body exudates. Given this purpose, it is quite often the
case that such body exudates escape the boundaries of the article as a result of leakage
from a point where the article contacts the skin or from seepage through the material
that makes up the absorbent article. The latter instance is often caused by the inability
of the materials of the article to serve as effective barriers to such bodily fluids.
[0003] The undesirable effects of leakage and/or improper containment, difficult cleanup,
and/or residual skin contamination are especially evident with regard to fecal matter
deposited in a diaper. Feces contained in the diaper can harm the skin of the wearer
over time and feces leaking from the diaper almost invariably presents unpleasant,
messy clean-ups. Thus, several attempts have been made to add features to diapers
such as barriers, pockets, spacers, transverse barriers, apertured topsheets and the
like to limit the movement of the fecal material across the topsheet and/or to better
confine the fecal matter in the diaper. Such attempts have been generally unsuccessful
because they fail to address the fundamental causes of these problems (i.e., the properties
of feces) and, because of their cost and complexity. Further, many of the means for
isolating or containing feces are directed to fecal material with certain physical
properties (e.g., viscosity, free water content and particle size) and are not effective
with exudates with physical properties outside a very small range.
[0004] Accordingly, it would be desirable to provide an absorbent article.with improved
low surface energy fluid management capabilities, particularly for feces management.
Further, it would be advantageous to provide an economical disposable article with
the ability to minimize the negative effects of feces or other viscous bodily waste
on the wearer or the caregiver. It would also be advantageous to provide an article
which is designed to chemically or physically interact with materials making up the
article and in order to reduce the amount of leakage and/or seepage that may occur.
SUMMARY OF THE INVENTION
[0005] In order to help resolve at least some of the problems described above, the present
invention provides an article which comprises:
- a. a liquid pervious first topsheet having an interior surface and an exterior surface;
- b. a backsheet having an interior surface and an exterior surface wherein said backsheet
is attached to said topsheet along a periphery;
- c. an absorbent core disposed between said topsheet and said backsheet;
- d. an additional article component selected from the group consisting of a core cover,
a diaper outer cover, an ear, a first cuff, a second cuff, a belt, a wing, an elasticized
topsheet, and combinations thereof; wherein said component has an interior and an
exterior surface; and
- e. a hydrophobic surface coating disposed on at least one surface of said backsheet
or said additional article component wherein said coating comprises a combination
of selected silicone polymers and wherein said coating is free of aminosilicones,
as described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006]
FIG. 1 shows a plan view of the absorbent article of the present invention.
FIG. 2 shows a perspective view of an absorbent article of the present invention.
FIG. 3 shows a cross-sectional view of the absorbent article depicted in FIG. 2.
FIG. 4. illustrates a component of the present article prior to treatment with the
hydrophobic surface coating of the present invention.
FIG. 5 illustrates a component of an article of the present invention that has been
treated with a hydrophobic surface coating according to the present invention.
FIG. 6 illustrates a component of an article of the present invention that has been
treated with another hydrophobic surface coating according to the present invention.
FIG. 7 illustrates via a perspective view another embodiment of the present invention
in which the hydrophobic surface coating has been applied to at least an elasticized
topsheet of an absorbent article.
DETAILED DESCRIPTION OF THE INVENTION
[0007] For the present invention, detailed herein are various definitions which are intended
to aid in the interpretation of the claimed subject matter.
[0008] As used herein, the term "absorbent article" refers to devices which absorb and contain
body exudates, and more specifically, refers to devices which are placed against or
in proximity to the body of the wearer to absorb and contain the various exudates
discharged from the body. Such devices include, but are not limited to, diapers, training
pants, adult incontinence products, sanitary napkins, and pantiliners.
[0009] As used herein, the term "diaper" refers to an absorbent article generally worn by
infants, and incontinent persons that is worn about the lower torso of the wearer.
In other words, the term "diaper" includes infant diapers, training pants, adult incontinence
devices, etc.
[0010] As used herein, the term "disposable" refers to absorbent articles which generally
are not intended to be laundered or otherwise restored or reused as an absorbent article
(i.e., they are intended to be discarded after a single use and, preferably, to be
recycled, composted or otherwise disposed of in an environmentally compatible manner).
[0011] As used herein, the term "telomer" refers to an addition polymer, usually of low
molecular weight, in which the growth of molecules is terminated by a radical-supplying
chain transfer agent or a low molecular weight polymer in which the terminal group
on the end of the chain-like molecule is not the same as the side group. Telomer may
also be used synonymously with oligomer, which is a polymer with very few (two to
ten) repeating units.
[0012] As used herein, the term "disposed" is used to mean that an element(s) of the diaper
is formed (joined or positioned) in a particular place or position as a unitary structure
with other elements of the diaper or as a separate element joined to another element
of the diaper.
[0013] As used herein, the term "joined" encompasses configurations whereby an element is
directly secured to another element by affixing the element directly to the other
element, and configurations whereby an element is indirectly secured to another element
by affixing the element to intermediate member(s) which in turn are affixed to the
other element.)
[0014] A "unitary" absorbent article refers to absorbent articles which are formed of separate
parts united together to form a coordinated entity so that they do not require separate
manipulative parts like a separate holder and liner.
[0015] As used herein, the term "comprising" means that the various components, ingredients,
or steps, can be conjointly employed in practicing the present invention. Accordingly,
the term "comprising" encompasses the more restrictive terms "consisting essentially
of" and "consisting of."
[0016] All percentages, ratios and proportions used herein are by weight unless otherwise
specified.
Absorbent Article
[0017] The disposable absorbent articles of the present invention comprise a liquid pervious
first topsheet, a backsheet attached or joined to the topsheet and an absorbent core
positioned between the topsheet and the backsheet. Disposable absorbent articles and
components thereof, including the topsheet, backsheet, absorbent core, and any individual
layers of these components, have an interior surface (or body surface) and an exterior
surface (or garment surface). As used herein, "interior surface" or "body surface"
means that surface of the article or component which is intended to be worn toward
or adjacent to the body of the wearer, while the "exterior surface" or "garment surface"
is on the opposite side and is intended to be worn toward or placed adjacent to the
undergarments when the disposable absorbent article is worn.
[0018] The following description generally discusses the absorbent core, first topsheet,
and backsheet materials that are useful in disposable absorbent articles. It is to
be understood that this general description applies to these components of the specific
absorbent article shown in FIG. 1 and further described below, in addition to those
of other disposable absorbent articles which are generally described herein.
[0019] FIG. 1 is a plan view of the diaper
50 of the present invention in its flat-out, uncontracted state (i.e., with elastic
induced contraction pulled out) with portions of the structure being cut-away to more
clearly show the construction of the diaper
50 and with the portion of the diaper
50 which faces away from the wearer, the outer surface, oriented towards the viewer.
As shown in FIG. 1, the diaper
50 preferably comprises a liquid pervious first topsheet
520; a liquid impervious backsheet
530 joined with the topsheet
520; an absorbent core
540 positioned between the first topsheet
520 and the backsheet
530, the absorbent core
540 having a exterior surface (or garment facing surface)
542, an interior surface (or a body facing surface)
544, side edges
546, waist edges
548, and ears
549. The diaper
50 preferably further comprises a first cuff
550, a second cuff
511, and an additional cuff
512; an elastic waist feature multiply designated as
560 (also referred to herein as a waistband or belt); and a fastening system generally
multiply designated as
570.
[0020] The diaper
50 is shown in FIG. 1 to have an outer surface
52, an inner surface
54 opposed to the outer surface
52, a first waist region
56, a second waist region
58, and a periphery
51 which is defined by the outer edges of the diaper
50 in which the longitudinal edges are designated
55 and the end edges are designated
57. (While the skilled artisan will recognize that a diaper is usually described in terms
of having a pair of waist regions and a crotch region between the waist regions, in
this application, for simplicity of terminology, the diaper
50 is described as having only waist regions including a portion of the diaper which
would typically be designated as part of the crotch region). The inner surface
54 of the diaper
50 comprises that portion of the diaper
50 which is positioned adjacent to the wearer's body during use (i.e., the inner surface
54 generally is formed by at least a portion of the first topsheet
520 and other components that may be joined to the first topsheet
520). The outer surface
52 comprises that portion of the diaper
50 which is positioned away from the wearer's body (i.e., the outer surface
52 generally is formed by at least a portion of the backsheet
530 and other components that may be joined to the backsheet
530). (As used herein, the portion of the diaper
50 or component thereof which faces the wearer is also referred to as the body facing
surface. Similarly, the portion facing away from the wearer is also referred to herein
as the garment facing surface.) The first waist region
56 and the second waist region
58 extend, respectively, from the end edges
57 of the periphery
51 to the lateral centerline
53 of the diaper
50. FIG. 1 also shows the longitudinal centerline
59.
[0021] FIG. 2 shows a perspective view of the article of the present invention which includes
at least a first and second cuff wherein the backsheet and at least one of the additional
components has been treated with the hydrophobic surface coating. FIG. 3 merely depicts
a cross-sectional view of the diaper shown in FIG. 2.
ABSORBENT CORE
[0022] The absorbent core
540 may take on any size or shape that is compatible with the diaper
50. One preferred embodiment of the diaper
50 has an asymmetric, modified T-shaped absorbent core
540 having ears in the first waist region but a generally rectangular shape in the second
waist region. Exemplary absorbent structures for use as the absorbent core of the
present invention that have achieved wide acceptance and commercial success are described
in
US Pat. Nos. 4610678,
4673402,
4888231, and
4834735. The absorbent core may further comprise the dual core system containing an acquisition/distribution
core of chemically stiffened fibers positioned over an absorbent storage core as detailed
in
US Pat. Nos. 5234423 and
5147345.
[0023] In general, the absorbent core is capable of absorbing or retaining liquids (e.g.,
menses, urine, and/or other body exudates). The absorbent core is preferably compressible,
conformable, and non-irritating to the wearer's skin. The absorbent core may include
any of a wide variety of liquid-absorbent materials commonly used in absorbent articles,
such as comminuted wood pulp, which is generally referred to as airfelt. Examples
of other suitable absorbent materials for use in the absorbent core include creped
cellulose wadding; meltblown polymers including coform; chemically stiffened, modified
or cross-linked cellulosic fibers; synthetic fibers such as crimped polyester fibers;
peat moss; tissue including tissue wraps and tissue laminates; absorbent foams; absorbent
sponges; superabsorbent polymers; absorbent gelling materials; or any equivalent material
or combinations of materials, or mixtures of these.
[0024] The configuration and construction of the absorbent core may also be varied (e.g.,
the absorbent core may have varying caliper zones and/or have a profile so as to be
thicker in the center; hydrophilic gradients; gradients of the absorbent composite
of the present invention, superabsorbent gradients; or lower average density and lower
average basis weight zones, e.g., acquisition zones; or may comprise one or more layers
or structures). The total absorbent capacity of the absorbent core should, however,
be compatible with the design loading and the intended use of the absorbent article.
Further, the size and absorbent capacity of the absorbent core may be varied to accommodate
different uses such as diapers, incontinence pads, pantiliners, regular sanitary napkins,
and overnight sanitary napkins, and to accommodate wearers ranging from infants to
adults. The absorbent core can include other absorbent components that are often used
in absorbent articles, for example, a dusting layer, a wicking or acquisition layer,
or a secondary (e.g., an elasticized) topsheet for increasing the wearer's comfort.
TOPSHEET
[0025] The first topsheet
520 of diaper
50 is preferably made of a hydrophilic material that promotes rapid transfer of liquids
(e.g., urine, menses, and/or runny feces) through the topsheet. If the first topsheet
is made of a hydrophobic material, at least the upper surface of the topsheet is treated
to be hydrophilic so that liquids will transfer through the topsheet more rapidly.
This diminishes the likelihood that body exudates will flow off the topsheet rather
than being drawn through the topsheet and being absorbed by the absorbent core. The
first topsheet can be rendered hydrophilic by treating it with a surfactant. Suitable
methods for treating the topsheet with a surfactant include spraying the topsheet
material with the surfactant and immersing the material into the surfactant. A more
detailed discussion of such a treatment and hydrophilicity is contained in
US Pat. No. 4988344 and
US Pat. No. 4988345.
[0026] The topsheet is preferably pliant, soft feeling, and non-irritating to the wearer's
skin. Further, the topsheet is liquid pervious, permitting liquids (e.g., menses,
urine, and/or runny feces) to readily penetrate through its thickness. A suitable
topsheet may be manufactured from a wide range of materials such as woven and nonwoven
materials (e.g., a nonwoven web of fibers); polymeric materials such as apertured
formed thermoplastic films, apertured plastic films, and hydroformed thermoplastic
films; porous foams; reticulated foams; reticulated thermoplastic films; and thermoplastic
scrims. Suitable woven and nonwoven materials can be comprised of natural fibers (e.g.,
wood or cotton fibers), synthetic fibers (e.g., polymeric fibers such as polyester,
polypropylene, or polyethylene fibers) or from a combination of natural and synthetic
fibers. When the topsheet comprises a nonwoven web, the web may be manufactured by
a wide number of known techniques. For example, the web may be spunbonded, carded,
wet-laid, meltblown, hydroentangled, combinations of the above, or the like.
[0027] Additionally, articles according to the present invention may comprise topsheets
that are elasticized to provide storage compartments for body exudates, particularly
bowel movements. Such topsheets and articles containing them are detailed in
US 6482191. Such an elasticized topsheet
600 is shown in FIG. 7 in an additional embodiment of the present invention.
BACKSHEET
[0028] The backsheet is preferably impervious to low surface tension fluids (e.g., menses,
urine, and/or runny feces). As used herein, "low surface tension fluids" refers to
fluids having a surface tension of less than 0,072 N/m (72 dynes/cm), preferably less
than 0,060 N/m (60 dynes/cm), and even more preferably less than 0,055 Nm (55 dynes/cm),
and most preferably from 0,025 to 0,055 N/m (25 to 55 dynes/cm). The backsheet is
preferably manufactured from a thin plastic film, although other flexible liquid impervious
materials may also be used. As used herein, the term "flexible" refers to materials
which are compliant and that readily conform to the general shape and contours of
the human body. The backsheet prevents the exudates absorbed and contained in the
absorbent core from wetting articles which contact the absorbent article such as bedsheets,
pants, pajamas and undergarments. The backsheet may thus comprise a woven or nonwoven
material, polymeric films such as thermoplastic films of polyethylene or polypropylene,
or composite materials such as a film-coated nonwoven material. A suitable backsheet
is a polyethylene film having a thickness of from 0.012 mm (0.5 mils) to 0.051 mm
(2.0 mils). Exemplary polyethylene films are manufactured by Clopay Corporation of
Cincinnati, Ohio, under the designation P18-1401 and by Tredegar Film Products of
Terre Haute, Ind., under the designation XP-39385. The backsheet is preferably embossed
and/or matte finished and provides a more clothlike-appearance. Further, the backsheet
may permit vapors to escape from the absorbent core (i.e., the backsheet is breathable)
while still preventing exudates from passing through the backsheet. The size of the
backsheet is dictated by the size of the absorbent core and the exact absorbent article
design selected.
[0029] The backsheet and the first topsheet are positioned adjacent the garment surface
and the body surface, respectively, of the absorbent core. The absorbent core is preferably
joined with the topsheet, the backsheet, or both in any manner as is known by attachment
means (not shown in FIG. 1) such as those well known in the art. However, embodiments
of the present invention are envisioned wherein portions of the entire absorbent core
are unattached to one or both of the topsheet and the backsheet.
[0030] For example, the backsheet and/or the first topsheet may be secured to the absorbent
core or to each other by a uniform continuous layer of adhesive, a patterned layer
of adhesive, or an array of separate lines, spirals, or spots of adhesive. Adhesives
which have been found to be satisfactory are manufactured by Bostik-Findley of Milwaukee,
WI under the designation HL-24012031. The attachment means will preferably comprise
an open pattern network of filaments of adhesive as is disclosed in
US Pat. No. 4573986, issued to Minetola, et al. An exemplary attachment means of an open pattern network of filaments comprises several
lines of adhesive filaments swirled into a spiral pattern such as illustrated by the
apparatus and method shown in
US Pat. No. 3911173 issued to Sprague, Jr.;
US Pat. No. 4785996 issued to Zwieker, et al.; and
US Pat. No. 4842666 issued to Werenicz. Alternatively, the attachment means may comprise heat bonds, pressure bonds, ultrasonic
bonds, dynamic mechanical bonds, or any other suitable attachment means or combinations
of these attachment means as are known in the art.
ADDITIONAL COMPONENTS
[0031] In a preferred embodiment, the diaper
50 further comprises at least a first cuff
550 for providing improved containment of liquids and other body exudates; an elastic
waist feature
560 that provides improved fit and containment; and a fastening system
570 which forms a side closure which maintains the first waist region
56 and the second waist region
58 in an overlapping configuration such that lateral tensions are maintained around
the circumference of the diaper to maintain the diaper on the wearer. The diaper
50 may also comprise elasticized side panels (not shown) in the waist regions
56 and
58 to provide an elastically extensible feature that provides a more comfortable and
contouring fit and more effective application of the diaper
50.
[0032] The elasticized leg cuffs
550 can be constructed in a number of different configurations, including those described
in
US Pat. Nos. 3860003,
4636207,
4695278,
4704115,
4795454,
4900317,
4909803 (Reissued as USRE34920),
5085654,
5492751,
6476288 and
SIR H1630.
[0033] For example, diaper
50 may include one or more first cuffs
550 which provide improved containment of liquids and other body exudates. First cuffs
550 may also be referred to as outer leg cuff, leg bands, side flaps, leg cuffs or elastic
cuffs.
U.S. Pat. No. 3,860,003 describes a disposable diaper which provides a contractible leg opening having a
side flap and one or more elastic members to provide an elasticized leg cuff.
[0034] Additionally, diaper
50 may include one or more second cuffs
511 which also provide improved containment of liquids and other body exudates. Second
cuffs
511 may also be referred to as barrier leg cuffs, inner leg cuffs or "stand-up" elasticized
flaps.
U.S. Pat. Nos. 4,808,178 and
4,909,803 issued to Aziz et al. on Feb. 28, 1989 and Mar. 20, 1990, respectively, describe disposable diapers having "stand-up" elasticized
flaps that improve the containment of the leg regions.
[0036] Additional cuffs
512 may be provided in an article of the present invention as detailed in US Statutory
Invention Registration H1630, which published January 7, 1997.
[0037] FIG. 2 shows a perspective diagram of a diaper according to the present invention
which includes at least one or more first and second cuffs wherein at least one of
the cuffs has been coated with the hydrophobic surface coating.
[0038] FIG. 3 depicts a cross-sectional view of the diaper shown in FIG. 2. In certain embodiments,
the second cuff may not be necessary due to the use of the hydrophobic coating on
the first cuff.
[0039] The elasticized waist feature preferably comprises an elasticized waistband (not
shown) that may be constructed in a number of different configurations including those
described in
US Pat. Nos. 4515595,
5026364, and
5151092. This waistband or belt of the diaper or absorbent article may include a cutout of
some sort that allows for undisturbed placement of an infant's navel, which tends
to be sensitive for a time after birth. Preferably, this cutout is in the shape of
a semicircle but may be in any geometric shape that allows for a comfortable fit of
the infant's navel.
[0040] The elasticized side panels may be constructed in a number of configurations. Examples
of diapers with elasticized side panels positioned in the ears (or ear flaps) of the
diaper are disclosed in
US Pat. No. 4857067,
4381781,
4938753, and
5151092.
Hydrophobic Surface Coating
[0042] The disposable absorbent articles of the present invention additionally comprise
a hydrophobic surface coating that is disposed on at least one surface of one or more
of the various components of the article including, but not limited to, a core cover,
a diaper outer cover, an ear, a wing, belt, a backsheet, a first cuff, a second cuff,
and even combinations thereof. This hydrophobic surface coating comprises a combination
of silicone polymers, and is also free of aminosilicones, are selected from the group
consisting of vinyl-terminated polydimethsiloxanes, methyl hydrogen dimethylsiloxanes,
hydroxyl-terminated polydimethysiloxanes, organo-modified polydimethylsiloxanes.
[0043] Typically, the molecular weight of such silicone polymers should be at least about
4000 M
W, preferably at least about 10,000 M
W, more preferably at least about 15,000 M
W, even more preferably at least about 20,000 M
W, and most preferably at least about 25,000 M
W.
[0044] Without being limited by theory, Applicants have found that these hydrophobic surface
coatings, when applied to various absorbent article components, tend to envelope or
at least partially coat one or more fibrous structures of the component in such a
way that a cohesive, uniform film-like network is formed around the fibrous structures,
and partially fills the pore network of the fibrous structures. This film-like network
serves to increase the barrier properties of the component, particularly when exposed
to low surface energy fluids. The film-like network is illustrated in FIG. 4, 5, and
6. In FIG. 4, an uncoated 15 gsm fibrous meltblown nonwoven is depicted. In FIG. 5,
the nonwoven of FIG. 4 has been treated with a hydrophobic surface coating known as
PSA950, which is commercially available from GE Silicones. PSA950 is a pressure sensitive
adhesive which is a phenyl siloxane in solvent. Here, the film-like network has formed
between the fibrous structures of the nonwoven. Likewise, in FIG. 6, the uncoated
meltblown nonwoven of FIG. 4 is coated with a hydrophobic surface coating known as
C2-0563 fabric water repellant, which is commercially available from Dow Coming. Again,
it is clear that a film-like network is formed between the fibers and in the pores
of the nonwoven, thereby improving its barrier properties.
[0045] In certain embodiments of the present invention, the coating may be inherently elastomeric.
Accordingly, when deposited onto one or more surfaces of an absorbent article component,
the hydrophobic surface coating may additionally provide an elastic character to the
article component when stretched.
[0046] Additionally, although it is envisioned that the present invention is primarily directed
to absorbent personal care articles, it is easily foreseeable that the hydrophobic
surface coatings disclosed herein may also be disposed onto substrates utilized for
other purposes. For instance, treated substrates could be utilized in the manufacture
of various surgical or medical materials (e.g., gowns, drapes, shoe covers, and caps),
wipes (e.g., for car cleaning, lens cleaning, packaging, wet cleaning, and dust),
consumer clothing, etc.
[0047] Moreover, it is important to note that when the coating is deposited onto the article
component, it is preferred that the component is substantially free of polymers containing
melt additives selected from the group consisting of polydimethylsiloxanes, guerbet
esters, and combinations thereof.
TEST METHODS
Liquid Strike Through
[0048] The barrier performance of the coated substrates is determined by measuring the time
in which a liquid added to the surface of the substrate penetrates the surface of
the substrate. The test method conforms to the Edana method 150.4-99 using a Lister
SN L5725 Model 1998 with the following changes:
- 1. Reference absorbent pad consists of 10 layers of filter paper (100mm x 100mm Ahlstrom
Grade 989) supplied by Empirical Mfg. Co., Inc. (Cincinnati, OH 513-948-1616).
- 2. Simulated runny BM/urine fluid mixture consisting of 0.04% (w/v) tRiton-X-100 (CAS#
9002-93-1) aqueous solution with a surface tension of approximately 32±mN/m.
- 3. Prior to the start of each test, and in between each replicate, the Lister electrodes
are rinsed with a 0.9% NaCl aqueous solution.
[0049] An average liquid strike through is determined by dividing the sum of times by the
number of component samples that are tested. Typically, the number of samples will
be about 30, i.e., n=30.
[0050] In order to determine the increase of liquid strike through time that results, a
comparison is done of average liquid strike through time of coated samples versus
uncoated (or untreated) samples.
EXAMPLES
Example 1
[0051] A hydrophobic surface coating of the present invention is prepared by spraying, dipping,
or employing a kiss-roll process of an aqueous mixture of vinyl terminated polydimethylsiloxane
and methylhydrogen polydimethylsiloxane in a 30:1 ratio in order that the coating
is deposited on the substrate. Substrate nonwovens used in this example were 13 g/m
2 (gsm), 15 g/m
2 (gsm), 17 g/m
2 (gsm), 20 g/m
2 (gsm), 30 g/m
2 (gsm), and 34 g/m
2 (gsm) spun/melt/spun polypropylene nonwovens, and 15 g/m
2 (gsm) and 200 g/m
2 (gsm) melt polypropylene nonwovens, which are commercially available from various
suppliers. The aqueous mixture also contains a transition metal catalyst to facilitate
the self crosslinking of the PDMS polymers. The wet coated substrate is dried at 90°C
- 120°C for 0.1 - 1.0 minutes depending if the sample is coated via a commercial or
laboratory coating process and is then stored in a suitable container for later use.
Example 2
[0052] A nonwoven diaper cuff component treated with a hydrophobic surface coating is prepared.
A 10% solution of a vinyl terminated PDMS (commercially available from GE
[0053] Silicones as SM3200) and a methyl hydrogen PDMS (commercially available from GE Silicones
as SM3010) is prepared and mixed for 30 minutes. A typical cuff component (spun-melt
nonwoven, as detailed in
US Patent No. 5492751, is dipped into the solution and the excess liquid squeezed out via calendar roll
and the component dried in an air convection oven at a temperature of 90°C - 120°C
for a time no more than 45 seconds in order that the coating is deposited on the substrate.
The cuff material is incorporated into a diaper as detailed in
US Patent Nos. 3860003,
4636207,
4695278,
4704115,
4795454,
4900317,
4909803 (Reissued as USRE34920),
5085654,
5492751,
6476288 and
SIR H1630.
Example 3
[0054] A nonwoven diaper cuff and/or backsheet component treated with a hydrophobic surface
coating is prepared. A 10% solution of a hydroxyl terminated PDMS (commercially available
from GE Silicones as SM2245) and a methyl hydrogen PDMS (commercially available from
GE Silicones as SM2014c) is prepared and mixed for 30 minutes. The cuff and/or backsheet
component, comprised of spun-melt nonwoven as detailed in
US Patent No. 5492751, is dipped into the solution and the excess liquid squeezed out via calendar roll
and the component dried in an air convection oven at a temperature of 90°C-120°C for
a time no more than 45 seconds in order that the coating is deposited on the substrate
and incorporated into a diaper as detailed in
US Patent Nos. 3860003,
4636207,
4695278,
4704115,
4795454,
4900317,
4909803 (Reissued as USRE34920),
5085654,
5492751,
6476288 and
SIR H1630.